1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 /*
27 * This file contains the top half of the zfs directory structure
28 * implementation. The bottom half is in zap_leaf.c.
29 *
30 * The zdir is an extendable hash data structure. There is a table of
31 * pointers to buckets (zap_t->zd_data->zd_leafs). The buckets are
32 * each a constant size and hold a variable number of directory entries.
33 * The buckets (aka "leaf nodes") are implemented in zap_leaf.c.
34 *
35 * The pointer table holds a power of 2 number of pointers.
36 * (1<<zap_t->zd_data->zd_phys->zd_prefix_len). The bucket pointed to
37 * by the pointer at index i in the table holds entries whose hash value
38 * has a zd_prefix_len - bit prefix
39 */
40
41 #include <sys/spa.h>
42 #include <sys/dmu.h>
43 #include <sys/zfs_context.h>
44 #include <sys/zfs_znode.h>
45 #include <sys/fs/zfs.h>
46 #include <sys/zap.h>
47 #include <sys/refcount.h>
48 #include <sys/zap_impl.h>
49 #include <sys/zap_leaf.h>
50
51 int fzap_default_block_shift = 14; /* 16k blocksize */
52
53 static void zap_leaf_pageout(dmu_buf_t *db, void *vl);
54 static uint64_t zap_allocate_blocks(zap_t *zap, int nblocks);
55
56
57 void
fzap_byteswap(void * vbuf,size_t size)58 fzap_byteswap(void *vbuf, size_t size)
59 {
60 uint64_t block_type;
61
62 block_type = *(uint64_t *)vbuf;
63
64 if (block_type == ZBT_LEAF || block_type == BSWAP_64(ZBT_LEAF))
65 zap_leaf_byteswap(vbuf, size);
66 else {
67 /* it's a ptrtbl block */
68 byteswap_uint64_array(vbuf, size);
69 }
70 }
71
72 void
fzap_upgrade(zap_t * zap,dmu_tx_t * tx,zap_flags_t flags)73 fzap_upgrade(zap_t *zap, dmu_tx_t *tx, zap_flags_t flags)
74 {
75 dmu_buf_t *db;
76 zap_leaf_t *l;
77 int i;
78 zap_phys_t *zp;
79
80 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
81 zap->zap_ismicro = FALSE;
82
83 (void) dmu_buf_update_user(zap->zap_dbuf, zap, zap,
84 &zap->zap_f.zap_phys, zap_evict);
85
86 mutex_init(&zap->zap_f.zap_num_entries_mtx, 0, 0, 0);
87 zap->zap_f.zap_block_shift = highbit(zap->zap_dbuf->db_size) - 1;
88
89 zp = zap->zap_f.zap_phys;
90 /*
91 * explicitly zero it since it might be coming from an
92 * initialized microzap
93 */
94 bzero(zap->zap_dbuf->db_data, zap->zap_dbuf->db_size);
95 zp->zap_block_type = ZBT_HEADER;
96 zp->zap_magic = ZAP_MAGIC;
97
98 zp->zap_ptrtbl.zt_shift = ZAP_EMBEDDED_PTRTBL_SHIFT(zap);
99
100 zp->zap_freeblk = 2; /* block 1 will be the first leaf */
101 zp->zap_num_leafs = 1;
102 zp->zap_num_entries = 0;
103 zp->zap_salt = zap->zap_salt;
104 zp->zap_normflags = zap->zap_normflags;
105 zp->zap_flags = flags;
106
107 /* block 1 will be the first leaf */
108 for (i = 0; i < (1<<zp->zap_ptrtbl.zt_shift); i++)
109 ZAP_EMBEDDED_PTRTBL_ENT(zap, i) = 1;
110
111 /*
112 * set up block 1 - the first leaf
113 */
114 VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object,
115 1<<FZAP_BLOCK_SHIFT(zap), FTAG, &db));
116 dmu_buf_will_dirty(db, tx);
117
118 l = kmem_zalloc(sizeof (zap_leaf_t), KM_SLEEP);
119 l->l_dbuf = db;
120 l->l_phys = db->db_data;
121
122 zap_leaf_init(l, zp->zap_normflags != 0);
123
124 kmem_free(l, sizeof (zap_leaf_t));
125 dmu_buf_rele(db, FTAG);
126 }
127
128 static int
zap_tryupgradedir(zap_t * zap,dmu_tx_t * tx)129 zap_tryupgradedir(zap_t *zap, dmu_tx_t *tx)
130 {
131 if (RW_WRITE_HELD(&zap->zap_rwlock))
132 return (1);
133 if (rw_tryupgrade(&zap->zap_rwlock)) {
134 dmu_buf_will_dirty(zap->zap_dbuf, tx);
135 return (1);
136 }
137 return (0);
138 }
139
140 /*
141 * Generic routines for dealing with the pointer & cookie tables.
142 */
143
144 static int
zap_table_grow(zap_t * zap,zap_table_phys_t * tbl,void (* transfer_func)(const uint64_t * src,uint64_t * dst,int n),dmu_tx_t * tx)145 zap_table_grow(zap_t *zap, zap_table_phys_t *tbl,
146 void (*transfer_func)(const uint64_t *src, uint64_t *dst, int n),
147 dmu_tx_t *tx)
148 {
149 uint64_t b, newblk;
150 dmu_buf_t *db_old, *db_new;
151 int err;
152 int bs = FZAP_BLOCK_SHIFT(zap);
153 int hepb = 1<<(bs-4);
154 /* hepb = half the number of entries in a block */
155
156 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
157 ASSERT(tbl->zt_blk != 0);
158 ASSERT(tbl->zt_numblks > 0);
159
160 if (tbl->zt_nextblk != 0) {
161 newblk = tbl->zt_nextblk;
162 } else {
163 newblk = zap_allocate_blocks(zap, tbl->zt_numblks * 2);
164 tbl->zt_nextblk = newblk;
165 ASSERT3U(tbl->zt_blks_copied, ==, 0);
166 dmu_prefetch(zap->zap_objset, zap->zap_object,
167 tbl->zt_blk << bs, tbl->zt_numblks << bs);
168 }
169
170 /*
171 * Copy the ptrtbl from the old to new location.
172 */
173
174 b = tbl->zt_blks_copied;
175 err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
176 (tbl->zt_blk + b) << bs, FTAG, &db_old);
177 if (err)
178 return (err);
179
180 /* first half of entries in old[b] go to new[2*b+0] */
181 VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object,
182 (newblk + 2*b+0) << bs, FTAG, &db_new));
183 dmu_buf_will_dirty(db_new, tx);
184 transfer_func(db_old->db_data, db_new->db_data, hepb);
185 dmu_buf_rele(db_new, FTAG);
186
187 /* second half of entries in old[b] go to new[2*b+1] */
188 VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object,
189 (newblk + 2*b+1) << bs, FTAG, &db_new));
190 dmu_buf_will_dirty(db_new, tx);
191 transfer_func((uint64_t *)db_old->db_data + hepb,
192 db_new->db_data, hepb);
193 dmu_buf_rele(db_new, FTAG);
194
195 dmu_buf_rele(db_old, FTAG);
196
197 tbl->zt_blks_copied++;
198
199 dprintf("copied block %llu of %llu\n",
200 tbl->zt_blks_copied, tbl->zt_numblks);
201
202 if (tbl->zt_blks_copied == tbl->zt_numblks) {
203 (void) dmu_free_range(zap->zap_objset, zap->zap_object,
204 tbl->zt_blk << bs, tbl->zt_numblks << bs, tx);
205
206 tbl->zt_blk = newblk;
207 tbl->zt_numblks *= 2;
208 tbl->zt_shift++;
209 tbl->zt_nextblk = 0;
210 tbl->zt_blks_copied = 0;
211
212 dprintf("finished; numblocks now %llu (%lluk entries)\n",
213 tbl->zt_numblks, 1<<(tbl->zt_shift-10));
214 }
215
216 return (0);
217 }
218
219 static int
zap_table_store(zap_t * zap,zap_table_phys_t * tbl,uint64_t idx,uint64_t val,dmu_tx_t * tx)220 zap_table_store(zap_t *zap, zap_table_phys_t *tbl, uint64_t idx, uint64_t val,
221 dmu_tx_t *tx)
222 {
223 int err;
224 uint64_t blk, off;
225 int bs = FZAP_BLOCK_SHIFT(zap);
226 dmu_buf_t *db;
227
228 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
229 ASSERT(tbl->zt_blk != 0);
230
231 dprintf("storing %llx at index %llx\n", val, idx);
232
233 blk = idx >> (bs-3);
234 off = idx & ((1<<(bs-3))-1);
235
236 err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
237 (tbl->zt_blk + blk) << bs, FTAG, &db);
238 if (err)
239 return (err);
240 dmu_buf_will_dirty(db, tx);
241
242 if (tbl->zt_nextblk != 0) {
243 uint64_t idx2 = idx * 2;
244 uint64_t blk2 = idx2 >> (bs-3);
245 uint64_t off2 = idx2 & ((1<<(bs-3))-1);
246 dmu_buf_t *db2;
247
248 err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
249 (tbl->zt_nextblk + blk2) << bs, FTAG, &db2);
250 if (err) {
251 dmu_buf_rele(db, FTAG);
252 return (err);
253 }
254 dmu_buf_will_dirty(db2, tx);
255 ((uint64_t *)db2->db_data)[off2] = val;
256 ((uint64_t *)db2->db_data)[off2+1] = val;
257 dmu_buf_rele(db2, FTAG);
258 }
259
260 ((uint64_t *)db->db_data)[off] = val;
261 dmu_buf_rele(db, FTAG);
262
263 return (0);
264 }
265
266 static int
zap_table_load(zap_t * zap,zap_table_phys_t * tbl,uint64_t idx,uint64_t * valp)267 zap_table_load(zap_t *zap, zap_table_phys_t *tbl, uint64_t idx, uint64_t *valp)
268 {
269 uint64_t blk, off;
270 int err;
271 dmu_buf_t *db;
272 int bs = FZAP_BLOCK_SHIFT(zap);
273
274 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
275
276 blk = idx >> (bs-3);
277 off = idx & ((1<<(bs-3))-1);
278
279 err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
280 (tbl->zt_blk + blk) << bs, FTAG, &db);
281 if (err)
282 return (err);
283 *valp = ((uint64_t *)db->db_data)[off];
284 dmu_buf_rele(db, FTAG);
285
286 if (tbl->zt_nextblk != 0) {
287 /*
288 * read the nextblk for the sake of i/o error checking,
289 * so that zap_table_load() will catch errors for
290 * zap_table_store.
291 */
292 blk = (idx*2) >> (bs-3);
293
294 err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
295 (tbl->zt_nextblk + blk) << bs, FTAG, &db);
296 dmu_buf_rele(db, FTAG);
297 }
298 return (err);
299 }
300
301 /*
302 * Routines for growing the ptrtbl.
303 */
304
305 static void
zap_ptrtbl_transfer(const uint64_t * src,uint64_t * dst,int n)306 zap_ptrtbl_transfer(const uint64_t *src, uint64_t *dst, int n)
307 {
308 int i;
309 for (i = 0; i < n; i++) {
310 uint64_t lb = src[i];
311 dst[2*i+0] = lb;
312 dst[2*i+1] = lb;
313 }
314 }
315
316 static int
zap_grow_ptrtbl(zap_t * zap,dmu_tx_t * tx)317 zap_grow_ptrtbl(zap_t *zap, dmu_tx_t *tx)
318 {
319 /*
320 * The pointer table should never use more hash bits than we
321 * have (otherwise we'd be using useless zero bits to index it).
322 * If we are within 2 bits of running out, stop growing, since
323 * this is already an aberrant condition.
324 */
325 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_shift >= zap_hashbits(zap) - 2)
326 return (ENOSPC);
327
328 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks == 0) {
329 /*
330 * We are outgrowing the "embedded" ptrtbl (the one
331 * stored in the header block). Give it its own entire
332 * block, which will double the size of the ptrtbl.
333 */
334 uint64_t newblk;
335 dmu_buf_t *db_new;
336 int err;
337
338 ASSERT3U(zap->zap_f.zap_phys->zap_ptrtbl.zt_shift, ==,
339 ZAP_EMBEDDED_PTRTBL_SHIFT(zap));
340 ASSERT3U(zap->zap_f.zap_phys->zap_ptrtbl.zt_blk, ==, 0);
341
342 newblk = zap_allocate_blocks(zap, 1);
343 err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
344 newblk << FZAP_BLOCK_SHIFT(zap), FTAG, &db_new);
345 if (err)
346 return (err);
347 dmu_buf_will_dirty(db_new, tx);
348 zap_ptrtbl_transfer(&ZAP_EMBEDDED_PTRTBL_ENT(zap, 0),
349 db_new->db_data, 1 << ZAP_EMBEDDED_PTRTBL_SHIFT(zap));
350 dmu_buf_rele(db_new, FTAG);
351
352 zap->zap_f.zap_phys->zap_ptrtbl.zt_blk = newblk;
353 zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks = 1;
354 zap->zap_f.zap_phys->zap_ptrtbl.zt_shift++;
355
356 ASSERT3U(1ULL << zap->zap_f.zap_phys->zap_ptrtbl.zt_shift, ==,
357 zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks <<
358 (FZAP_BLOCK_SHIFT(zap)-3));
359
360 return (0);
361 } else {
362 return (zap_table_grow(zap, &zap->zap_f.zap_phys->zap_ptrtbl,
363 zap_ptrtbl_transfer, tx));
364 }
365 }
366
367 static void
zap_increment_num_entries(zap_t * zap,int delta,dmu_tx_t * tx)368 zap_increment_num_entries(zap_t *zap, int delta, dmu_tx_t *tx)
369 {
370 dmu_buf_will_dirty(zap->zap_dbuf, tx);
371 mutex_enter(&zap->zap_f.zap_num_entries_mtx);
372 ASSERT(delta > 0 || zap->zap_f.zap_phys->zap_num_entries >= -delta);
373 zap->zap_f.zap_phys->zap_num_entries += delta;
374 mutex_exit(&zap->zap_f.zap_num_entries_mtx);
375 }
376
377 static uint64_t
zap_allocate_blocks(zap_t * zap,int nblocks)378 zap_allocate_blocks(zap_t *zap, int nblocks)
379 {
380 uint64_t newblk;
381 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
382 newblk = zap->zap_f.zap_phys->zap_freeblk;
383 zap->zap_f.zap_phys->zap_freeblk += nblocks;
384 return (newblk);
385 }
386
387 static zap_leaf_t *
zap_create_leaf(zap_t * zap,dmu_tx_t * tx)388 zap_create_leaf(zap_t *zap, dmu_tx_t *tx)
389 {
390 void *winner;
391 zap_leaf_t *l = kmem_alloc(sizeof (zap_leaf_t), KM_SLEEP);
392
393 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
394
395 rw_init(&l->l_rwlock, 0, 0, 0);
396 rw_enter(&l->l_rwlock, RW_WRITER);
397 l->l_blkid = zap_allocate_blocks(zap, 1);
398 l->l_dbuf = NULL;
399 l->l_phys = NULL;
400
401 VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object,
402 l->l_blkid << FZAP_BLOCK_SHIFT(zap), NULL, &l->l_dbuf));
403 winner = dmu_buf_set_user(l->l_dbuf, l, &l->l_phys, zap_leaf_pageout);
404 ASSERT(winner == NULL);
405 dmu_buf_will_dirty(l->l_dbuf, tx);
406
407 zap_leaf_init(l, zap->zap_normflags != 0);
408
409 zap->zap_f.zap_phys->zap_num_leafs++;
410
411 return (l);
412 }
413
414 int
fzap_count(zap_t * zap,uint64_t * count)415 fzap_count(zap_t *zap, uint64_t *count)
416 {
417 ASSERT(!zap->zap_ismicro);
418 mutex_enter(&zap->zap_f.zap_num_entries_mtx); /* unnecessary */
419 *count = zap->zap_f.zap_phys->zap_num_entries;
420 mutex_exit(&zap->zap_f.zap_num_entries_mtx);
421 return (0);
422 }
423
424 /*
425 * Routines for obtaining zap_leaf_t's
426 */
427
428 void
zap_put_leaf(zap_leaf_t * l)429 zap_put_leaf(zap_leaf_t *l)
430 {
431 rw_exit(&l->l_rwlock);
432 dmu_buf_rele(l->l_dbuf, NULL);
433 }
434
435 _NOTE(ARGSUSED(0))
436 static void
zap_leaf_pageout(dmu_buf_t * db,void * vl)437 zap_leaf_pageout(dmu_buf_t *db, void *vl)
438 {
439 zap_leaf_t *l = vl;
440
441 rw_destroy(&l->l_rwlock);
442 kmem_free(l, sizeof (zap_leaf_t));
443 }
444
445 static zap_leaf_t *
zap_open_leaf(uint64_t blkid,dmu_buf_t * db)446 zap_open_leaf(uint64_t blkid, dmu_buf_t *db)
447 {
448 zap_leaf_t *l, *winner;
449
450 ASSERT(blkid != 0);
451
452 l = kmem_alloc(sizeof (zap_leaf_t), KM_SLEEP);
453 rw_init(&l->l_rwlock, 0, 0, 0);
454 rw_enter(&l->l_rwlock, RW_WRITER);
455 l->l_blkid = blkid;
456 l->l_bs = highbit(db->db_size)-1;
457 l->l_dbuf = db;
458 l->l_phys = NULL;
459
460 winner = dmu_buf_set_user(db, l, &l->l_phys, zap_leaf_pageout);
461
462 rw_exit(&l->l_rwlock);
463 if (winner != NULL) {
464 /* someone else set it first */
465 zap_leaf_pageout(NULL, l);
466 l = winner;
467 }
468
469 /*
470 * lhr_pad was previously used for the next leaf in the leaf
471 * chain. There should be no chained leafs (as we have removed
472 * support for them).
473 */
474 ASSERT3U(l->l_phys->l_hdr.lh_pad1, ==, 0);
475
476 /*
477 * There should be more hash entries than there can be
478 * chunks to put in the hash table
479 */
480 ASSERT3U(ZAP_LEAF_HASH_NUMENTRIES(l), >, ZAP_LEAF_NUMCHUNKS(l) / 3);
481
482 /* The chunks should begin at the end of the hash table */
483 ASSERT3P(&ZAP_LEAF_CHUNK(l, 0), ==,
484 &l->l_phys->l_hash[ZAP_LEAF_HASH_NUMENTRIES(l)]);
485
486 /* The chunks should end at the end of the block */
487 ASSERT3U((uintptr_t)&ZAP_LEAF_CHUNK(l, ZAP_LEAF_NUMCHUNKS(l)) -
488 (uintptr_t)l->l_phys, ==, l->l_dbuf->db_size);
489
490 return (l);
491 }
492
493 static int
zap_get_leaf_byblk(zap_t * zap,uint64_t blkid,dmu_tx_t * tx,krw_t lt,zap_leaf_t ** lp)494 zap_get_leaf_byblk(zap_t *zap, uint64_t blkid, dmu_tx_t *tx, krw_t lt,
495 zap_leaf_t **lp)
496 {
497 dmu_buf_t *db;
498 zap_leaf_t *l;
499 int bs = FZAP_BLOCK_SHIFT(zap);
500 int err;
501
502 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
503
504 err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
505 blkid << bs, NULL, &db);
506 if (err)
507 return (err);
508
509 ASSERT3U(db->db_object, ==, zap->zap_object);
510 ASSERT3U(db->db_offset, ==, blkid << bs);
511 ASSERT3U(db->db_size, ==, 1 << bs);
512 ASSERT(blkid != 0);
513
514 l = dmu_buf_get_user(db);
515
516 if (l == NULL)
517 l = zap_open_leaf(blkid, db);
518
519 rw_enter(&l->l_rwlock, lt);
520 /*
521 * Must lock before dirtying, otherwise l->l_phys could change,
522 * causing ASSERT below to fail.
523 */
524 if (lt == RW_WRITER)
525 dmu_buf_will_dirty(db, tx);
526 ASSERT3U(l->l_blkid, ==, blkid);
527 ASSERT3P(l->l_dbuf, ==, db);
528 ASSERT3P(l->l_phys, ==, l->l_dbuf->db_data);
529 ASSERT3U(l->l_phys->l_hdr.lh_block_type, ==, ZBT_LEAF);
530 ASSERT3U(l->l_phys->l_hdr.lh_magic, ==, ZAP_LEAF_MAGIC);
531
532 *lp = l;
533 return (0);
534 }
535
536 static int
zap_idx_to_blk(zap_t * zap,uint64_t idx,uint64_t * valp)537 zap_idx_to_blk(zap_t *zap, uint64_t idx, uint64_t *valp)
538 {
539 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
540
541 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks == 0) {
542 ASSERT3U(idx, <,
543 (1ULL << zap->zap_f.zap_phys->zap_ptrtbl.zt_shift));
544 *valp = ZAP_EMBEDDED_PTRTBL_ENT(zap, idx);
545 return (0);
546 } else {
547 return (zap_table_load(zap, &zap->zap_f.zap_phys->zap_ptrtbl,
548 idx, valp));
549 }
550 }
551
552 static int
zap_set_idx_to_blk(zap_t * zap,uint64_t idx,uint64_t blk,dmu_tx_t * tx)553 zap_set_idx_to_blk(zap_t *zap, uint64_t idx, uint64_t blk, dmu_tx_t *tx)
554 {
555 ASSERT(tx != NULL);
556 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
557
558 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_blk == 0) {
559 ZAP_EMBEDDED_PTRTBL_ENT(zap, idx) = blk;
560 return (0);
561 } else {
562 return (zap_table_store(zap, &zap->zap_f.zap_phys->zap_ptrtbl,
563 idx, blk, tx));
564 }
565 }
566
567 static int
zap_deref_leaf(zap_t * zap,uint64_t h,dmu_tx_t * tx,krw_t lt,zap_leaf_t ** lp)568 zap_deref_leaf(zap_t *zap, uint64_t h, dmu_tx_t *tx, krw_t lt, zap_leaf_t **lp)
569 {
570 uint64_t idx, blk;
571 int err;
572
573 ASSERT(zap->zap_dbuf == NULL ||
574 zap->zap_f.zap_phys == zap->zap_dbuf->db_data);
575 ASSERT3U(zap->zap_f.zap_phys->zap_magic, ==, ZAP_MAGIC);
576 idx = ZAP_HASH_IDX(h, zap->zap_f.zap_phys->zap_ptrtbl.zt_shift);
577 err = zap_idx_to_blk(zap, idx, &blk);
578 if (err != 0)
579 return (err);
580 err = zap_get_leaf_byblk(zap, blk, tx, lt, lp);
581
582 ASSERT(err || ZAP_HASH_IDX(h, (*lp)->l_phys->l_hdr.lh_prefix_len) ==
583 (*lp)->l_phys->l_hdr.lh_prefix);
584 return (err);
585 }
586
587 static int
zap_expand_leaf(zap_name_t * zn,zap_leaf_t * l,dmu_tx_t * tx,zap_leaf_t ** lp)588 zap_expand_leaf(zap_name_t *zn, zap_leaf_t *l, dmu_tx_t *tx, zap_leaf_t **lp)
589 {
590 zap_t *zap = zn->zn_zap;
591 uint64_t hash = zn->zn_hash;
592 zap_leaf_t *nl;
593 int prefix_diff, i, err;
594 uint64_t sibling;
595 int old_prefix_len = l->l_phys->l_hdr.lh_prefix_len;
596
597 ASSERT3U(old_prefix_len, <=, zap->zap_f.zap_phys->zap_ptrtbl.zt_shift);
598 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
599
600 ASSERT3U(ZAP_HASH_IDX(hash, old_prefix_len), ==,
601 l->l_phys->l_hdr.lh_prefix);
602
603 if (zap_tryupgradedir(zap, tx) == 0 ||
604 old_prefix_len == zap->zap_f.zap_phys->zap_ptrtbl.zt_shift) {
605 /* We failed to upgrade, or need to grow the pointer table */
606 objset_t *os = zap->zap_objset;
607 uint64_t object = zap->zap_object;
608
609 zap_put_leaf(l);
610 zap_unlockdir(zap);
611 err = zap_lockdir(os, object, tx, RW_WRITER,
612 FALSE, FALSE, &zn->zn_zap);
613 zap = zn->zn_zap;
614 if (err)
615 return (err);
616 ASSERT(!zap->zap_ismicro);
617
618 while (old_prefix_len ==
619 zap->zap_f.zap_phys->zap_ptrtbl.zt_shift) {
620 err = zap_grow_ptrtbl(zap, tx);
621 if (err)
622 return (err);
623 }
624
625 err = zap_deref_leaf(zap, hash, tx, RW_WRITER, &l);
626 if (err)
627 return (err);
628
629 if (l->l_phys->l_hdr.lh_prefix_len != old_prefix_len) {
630 /* it split while our locks were down */
631 *lp = l;
632 return (0);
633 }
634 }
635 ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
636 ASSERT3U(old_prefix_len, <, zap->zap_f.zap_phys->zap_ptrtbl.zt_shift);
637 ASSERT3U(ZAP_HASH_IDX(hash, old_prefix_len), ==,
638 l->l_phys->l_hdr.lh_prefix);
639
640 prefix_diff = zap->zap_f.zap_phys->zap_ptrtbl.zt_shift -
641 (old_prefix_len + 1);
642 sibling = (ZAP_HASH_IDX(hash, old_prefix_len + 1) | 1) << prefix_diff;
643
644 /* check for i/o errors before doing zap_leaf_split */
645 for (i = 0; i < (1ULL<<prefix_diff); i++) {
646 uint64_t blk;
647 err = zap_idx_to_blk(zap, sibling+i, &blk);
648 if (err)
649 return (err);
650 ASSERT3U(blk, ==, l->l_blkid);
651 }
652
653 nl = zap_create_leaf(zap, tx);
654 zap_leaf_split(l, nl, zap->zap_normflags != 0);
655
656 /* set sibling pointers */
657 for (i = 0; i < (1ULL<<prefix_diff); i++) {
658 err = zap_set_idx_to_blk(zap, sibling+i, nl->l_blkid, tx);
659 ASSERT3U(err, ==, 0); /* we checked for i/o errors above */
660 }
661
662 if (hash & (1ULL << (64 - l->l_phys->l_hdr.lh_prefix_len))) {
663 /* we want the sibling */
664 zap_put_leaf(l);
665 *lp = nl;
666 } else {
667 zap_put_leaf(nl);
668 *lp = l;
669 }
670
671 return (0);
672 }
673
674 static void
zap_put_leaf_maybe_grow_ptrtbl(zap_name_t * zn,zap_leaf_t * l,dmu_tx_t * tx)675 zap_put_leaf_maybe_grow_ptrtbl(zap_name_t *zn, zap_leaf_t *l, dmu_tx_t *tx)
676 {
677 zap_t *zap = zn->zn_zap;
678 int shift = zap->zap_f.zap_phys->zap_ptrtbl.zt_shift;
679 int leaffull = (l->l_phys->l_hdr.lh_prefix_len == shift &&
680 l->l_phys->l_hdr.lh_nfree < ZAP_LEAF_LOW_WATER);
681
682 zap_put_leaf(l);
683
684 if (leaffull || zap->zap_f.zap_phys->zap_ptrtbl.zt_nextblk) {
685 int err;
686
687 /*
688 * We are in the middle of growing the pointer table, or
689 * this leaf will soon make us grow it.
690 */
691 if (zap_tryupgradedir(zap, tx) == 0) {
692 objset_t *os = zap->zap_objset;
693 uint64_t zapobj = zap->zap_object;
694
695 zap_unlockdir(zap);
696 err = zap_lockdir(os, zapobj, tx,
697 RW_WRITER, FALSE, FALSE, &zn->zn_zap);
698 zap = zn->zn_zap;
699 if (err)
700 return;
701 }
702
703 /* could have finished growing while our locks were down */
704 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_shift == shift)
705 (void) zap_grow_ptrtbl(zap, tx);
706 }
707 }
708
709 static int
fzap_checkname(zap_name_t * zn)710 fzap_checkname(zap_name_t *zn)
711 {
712 if (zn->zn_key_orig_numints * zn->zn_key_intlen > ZAP_MAXNAMELEN)
713 return (ENAMETOOLONG);
714 return (0);
715 }
716
717 static int
fzap_checksize(uint64_t integer_size,uint64_t num_integers)718 fzap_checksize(uint64_t integer_size, uint64_t num_integers)
719 {
720 /* Only integer sizes supported by C */
721 switch (integer_size) {
722 case 1:
723 case 2:
724 case 4:
725 case 8:
726 break;
727 default:
728 return (EINVAL);
729 }
730
731 if (integer_size * num_integers > ZAP_MAXVALUELEN)
732 return (E2BIG);
733
734 return (0);
735 }
736
737 static int
fzap_check(zap_name_t * zn,uint64_t integer_size,uint64_t num_integers)738 fzap_check(zap_name_t *zn, uint64_t integer_size, uint64_t num_integers)
739 {
740 int err;
741
742 if ((err = fzap_checkname(zn)) != 0)
743 return (err);
744 return (fzap_checksize(integer_size, num_integers));
745 }
746
747 /*
748 * Routines for manipulating attributes.
749 */
750 int
fzap_lookup(zap_name_t * zn,uint64_t integer_size,uint64_t num_integers,void * buf,char * realname,int rn_len,boolean_t * ncp)751 fzap_lookup(zap_name_t *zn,
752 uint64_t integer_size, uint64_t num_integers, void *buf,
753 char *realname, int rn_len, boolean_t *ncp)
754 {
755 zap_leaf_t *l;
756 int err;
757 zap_entry_handle_t zeh;
758
759 if ((err = fzap_checkname(zn)) != 0)
760 return (err);
761
762 err = zap_deref_leaf(zn->zn_zap, zn->zn_hash, NULL, RW_READER, &l);
763 if (err != 0)
764 return (err);
765 err = zap_leaf_lookup(l, zn, &zeh);
766 if (err == 0) {
767 if ((err = fzap_checksize(integer_size, num_integers)) != 0) {
768 zap_put_leaf(l);
769 return (err);
770 }
771
772 err = zap_entry_read(&zeh, integer_size, num_integers, buf);
773 (void) zap_entry_read_name(zn->zn_zap, &zeh, rn_len, realname);
774 if (ncp) {
775 *ncp = zap_entry_normalization_conflict(&zeh,
776 zn, NULL, zn->zn_zap);
777 }
778 }
779
780 zap_put_leaf(l);
781 return (err);
782 }
783
784 int
fzap_add_cd(zap_name_t * zn,uint64_t integer_size,uint64_t num_integers,const void * val,uint32_t cd,dmu_tx_t * tx)785 fzap_add_cd(zap_name_t *zn,
786 uint64_t integer_size, uint64_t num_integers,
787 const void *val, uint32_t cd, dmu_tx_t *tx)
788 {
789 zap_leaf_t *l;
790 int err;
791 zap_entry_handle_t zeh;
792 zap_t *zap = zn->zn_zap;
793
794 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
795 ASSERT(!zap->zap_ismicro);
796 ASSERT(fzap_check(zn, integer_size, num_integers) == 0);
797
798 err = zap_deref_leaf(zap, zn->zn_hash, tx, RW_WRITER, &l);
799 if (err != 0)
800 return (err);
801 retry:
802 err = zap_leaf_lookup(l, zn, &zeh);
803 if (err == 0) {
804 err = EEXIST;
805 goto out;
806 }
807 if (err != ENOENT)
808 goto out;
809
810 err = zap_entry_create(l, zn, cd,
811 integer_size, num_integers, val, &zeh);
812
813 if (err == 0) {
814 zap_increment_num_entries(zap, 1, tx);
815 } else if (err == EAGAIN) {
816 err = zap_expand_leaf(zn, l, tx, &l);
817 zap = zn->zn_zap; /* zap_expand_leaf() may change zap */
818 if (err == 0)
819 goto retry;
820 }
821
822 out:
823 if (zap != NULL)
824 zap_put_leaf_maybe_grow_ptrtbl(zn, l, tx);
825 return (err);
826 }
827
828 int
fzap_add(zap_name_t * zn,uint64_t integer_size,uint64_t num_integers,const void * val,dmu_tx_t * tx)829 fzap_add(zap_name_t *zn,
830 uint64_t integer_size, uint64_t num_integers,
831 const void *val, dmu_tx_t *tx)
832 {
833 int err = fzap_check(zn, integer_size, num_integers);
834 if (err != 0)
835 return (err);
836
837 return (fzap_add_cd(zn, integer_size, num_integers,
838 val, ZAP_NEED_CD, tx));
839 }
840
841 int
fzap_update(zap_name_t * zn,int integer_size,uint64_t num_integers,const void * val,dmu_tx_t * tx)842 fzap_update(zap_name_t *zn,
843 int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx)
844 {
845 zap_leaf_t *l;
846 int err, create;
847 zap_entry_handle_t zeh;
848 zap_t *zap = zn->zn_zap;
849
850 ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
851 err = fzap_check(zn, integer_size, num_integers);
852 if (err != 0)
853 return (err);
854
855 err = zap_deref_leaf(zap, zn->zn_hash, tx, RW_WRITER, &l);
856 if (err != 0)
857 return (err);
858 retry:
859 err = zap_leaf_lookup(l, zn, &zeh);
860 create = (err == ENOENT);
861 ASSERT(err == 0 || err == ENOENT);
862
863 if (create) {
864 err = zap_entry_create(l, zn, ZAP_NEED_CD,
865 integer_size, num_integers, val, &zeh);
866 if (err == 0)
867 zap_increment_num_entries(zap, 1, tx);
868 } else {
869 err = zap_entry_update(&zeh, integer_size, num_integers, val);
870 }
871
872 if (err == EAGAIN) {
873 err = zap_expand_leaf(zn, l, tx, &l);
874 zap = zn->zn_zap; /* zap_expand_leaf() may change zap */
875 if (err == 0)
876 goto retry;
877 }
878
879 if (zap != NULL)
880 zap_put_leaf_maybe_grow_ptrtbl(zn, l, tx);
881 return (err);
882 }
883
884 int
fzap_length(zap_name_t * zn,uint64_t * integer_size,uint64_t * num_integers)885 fzap_length(zap_name_t *zn,
886 uint64_t *integer_size, uint64_t *num_integers)
887 {
888 zap_leaf_t *l;
889 int err;
890 zap_entry_handle_t zeh;
891
892 err = zap_deref_leaf(zn->zn_zap, zn->zn_hash, NULL, RW_READER, &l);
893 if (err != 0)
894 return (err);
895 err = zap_leaf_lookup(l, zn, &zeh);
896 if (err != 0)
897 goto out;
898
899 if (integer_size)
900 *integer_size = zeh.zeh_integer_size;
901 if (num_integers)
902 *num_integers = zeh.zeh_num_integers;
903 out:
904 zap_put_leaf(l);
905 return (err);
906 }
907
908 int
fzap_remove(zap_name_t * zn,dmu_tx_t * tx)909 fzap_remove(zap_name_t *zn, dmu_tx_t *tx)
910 {
911 zap_leaf_t *l;
912 int err;
913 zap_entry_handle_t zeh;
914
915 err = zap_deref_leaf(zn->zn_zap, zn->zn_hash, tx, RW_WRITER, &l);
916 if (err != 0)
917 return (err);
918 err = zap_leaf_lookup(l, zn, &zeh);
919 if (err == 0) {
920 zap_entry_remove(&zeh);
921 zap_increment_num_entries(zn->zn_zap, -1, tx);
922 }
923 zap_put_leaf(l);
924 return (err);
925 }
926
927 /*
928 * Helper functions for consumers.
929 */
930
931 int
zap_value_search(objset_t * os,uint64_t zapobj,uint64_t value,uint64_t mask,char * name)932 zap_value_search(objset_t *os, uint64_t zapobj, uint64_t value, uint64_t mask,
933 char *name)
934 {
935 zap_cursor_t zc;
936 zap_attribute_t *za;
937 int err;
938
939 if (mask == 0)
940 mask = -1ULL;
941
942 za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
943 for (zap_cursor_init(&zc, os, zapobj);
944 (err = zap_cursor_retrieve(&zc, za)) == 0;
945 zap_cursor_advance(&zc)) {
946 if ((za->za_first_integer & mask) == (value & mask)) {
947 (void) strcpy(name, za->za_name);
948 break;
949 }
950 }
951 zap_cursor_fini(&zc);
952 kmem_free(za, sizeof (zap_attribute_t));
953 return (err);
954 }
955
956 int
zap_join(objset_t * os,uint64_t fromobj,uint64_t intoobj,dmu_tx_t * tx)957 zap_join(objset_t *os, uint64_t fromobj, uint64_t intoobj, dmu_tx_t *tx)
958 {
959 zap_cursor_t zc;
960 zap_attribute_t za;
961 int err;
962
963 for (zap_cursor_init(&zc, os, fromobj);
964 zap_cursor_retrieve(&zc, &za) == 0;
965 (void) zap_cursor_advance(&zc)) {
966 if (za.za_integer_length != 8 || za.za_num_integers != 1)
967 return (EINVAL);
968 err = zap_add(os, intoobj, za.za_name,
969 8, 1, &za.za_first_integer, tx);
970 if (err)
971 return (err);
972 }
973 zap_cursor_fini(&zc);
974 return (0);
975 }
976
977 int
zap_add_int(objset_t * os,uint64_t obj,uint64_t value,dmu_tx_t * tx)978 zap_add_int(objset_t *os, uint64_t obj, uint64_t value, dmu_tx_t *tx)
979 {
980 char name[20];
981
982 (void) snprintf(name, sizeof (name), "%llx", (longlong_t)value);
983 return (zap_add(os, obj, name, 8, 1, &value, tx));
984 }
985
986 int
zap_remove_int(objset_t * os,uint64_t obj,uint64_t value,dmu_tx_t * tx)987 zap_remove_int(objset_t *os, uint64_t obj, uint64_t value, dmu_tx_t *tx)
988 {
989 char name[20];
990
991 (void) snprintf(name, sizeof (name), "%llx", (longlong_t)value);
992 return (zap_remove(os, obj, name, tx));
993 }
994
995 int
zap_lookup_int(objset_t * os,uint64_t obj,uint64_t value)996 zap_lookup_int(objset_t *os, uint64_t obj, uint64_t value)
997 {
998 char name[20];
999
1000 (void) snprintf(name, sizeof (name), "%llx", (longlong_t)value);
1001 return (zap_lookup(os, obj, name, 8, 1, &value));
1002 }
1003
1004 int
zap_increment_int(objset_t * os,uint64_t obj,uint64_t key,int64_t delta,dmu_tx_t * tx)1005 zap_increment_int(objset_t *os, uint64_t obj, uint64_t key, int64_t delta,
1006 dmu_tx_t *tx)
1007 {
1008 char name[20];
1009 uint64_t value = 0;
1010 int err;
1011
1012 if (delta == 0)
1013 return (0);
1014
1015 (void) snprintf(name, sizeof (name), "%llx", (longlong_t)key);
1016 err = zap_lookup(os, obj, name, 8, 1, &value);
1017 if (err != 0 && err != ENOENT)
1018 return (err);
1019 value += delta;
1020 if (value == 0)
1021 err = zap_remove(os, obj, name, tx);
1022 else
1023 err = zap_update(os, obj, name, 8, 1, &value, tx);
1024 return (err);
1025 }
1026
1027
1028 /*
1029 * Routines for iterating over the attributes.
1030 */
1031
1032 int
fzap_cursor_retrieve(zap_t * zap,zap_cursor_t * zc,zap_attribute_t * za)1033 fzap_cursor_retrieve(zap_t *zap, zap_cursor_t *zc, zap_attribute_t *za)
1034 {
1035 int err = ENOENT;
1036 zap_entry_handle_t zeh;
1037 zap_leaf_t *l;
1038
1039 /* retrieve the next entry at or after zc_hash/zc_cd */
1040 /* if no entry, return ENOENT */
1041
1042 if (zc->zc_leaf &&
1043 (ZAP_HASH_IDX(zc->zc_hash,
1044 zc->zc_leaf->l_phys->l_hdr.lh_prefix_len) !=
1045 zc->zc_leaf->l_phys->l_hdr.lh_prefix)) {
1046 rw_enter(&zc->zc_leaf->l_rwlock, RW_READER);
1047 zap_put_leaf(zc->zc_leaf);
1048 zc->zc_leaf = NULL;
1049 }
1050
1051 again:
1052 if (zc->zc_leaf == NULL) {
1053 err = zap_deref_leaf(zap, zc->zc_hash, NULL, RW_READER,
1054 &zc->zc_leaf);
1055 if (err != 0)
1056 return (err);
1057 } else {
1058 rw_enter(&zc->zc_leaf->l_rwlock, RW_READER);
1059 }
1060 l = zc->zc_leaf;
1061
1062 err = zap_leaf_lookup_closest(l, zc->zc_hash, zc->zc_cd, &zeh);
1063
1064 if (err == ENOENT) {
1065 uint64_t nocare =
1066 (1ULL << (64 - l->l_phys->l_hdr.lh_prefix_len)) - 1;
1067 zc->zc_hash = (zc->zc_hash & ~nocare) + nocare + 1;
1068 zc->zc_cd = 0;
1069 if (l->l_phys->l_hdr.lh_prefix_len == 0 || zc->zc_hash == 0) {
1070 zc->zc_hash = -1ULL;
1071 } else {
1072 zap_put_leaf(zc->zc_leaf);
1073 zc->zc_leaf = NULL;
1074 goto again;
1075 }
1076 }
1077
1078 if (err == 0) {
1079 zc->zc_hash = zeh.zeh_hash;
1080 zc->zc_cd = zeh.zeh_cd;
1081 za->za_integer_length = zeh.zeh_integer_size;
1082 za->za_num_integers = zeh.zeh_num_integers;
1083 if (zeh.zeh_num_integers == 0) {
1084 za->za_first_integer = 0;
1085 } else {
1086 err = zap_entry_read(&zeh, 8, 1, &za->za_first_integer);
1087 ASSERT(err == 0 || err == EOVERFLOW);
1088 }
1089 err = zap_entry_read_name(zap, &zeh,
1090 sizeof (za->za_name), za->za_name);
1091 ASSERT(err == 0);
1092
1093 za->za_normalization_conflict =
1094 zap_entry_normalization_conflict(&zeh,
1095 NULL, za->za_name, zap);
1096 }
1097 rw_exit(&zc->zc_leaf->l_rwlock);
1098 return (err);
1099 }
1100
1101
1102 static void
zap_stats_ptrtbl(zap_t * zap,uint64_t * tbl,int len,zap_stats_t * zs)1103 zap_stats_ptrtbl(zap_t *zap, uint64_t *tbl, int len, zap_stats_t *zs)
1104 {
1105 int i, err;
1106 uint64_t lastblk = 0;
1107
1108 /*
1109 * NB: if a leaf has more pointers than an entire ptrtbl block
1110 * can hold, then it'll be accounted for more than once, since
1111 * we won't have lastblk.
1112 */
1113 for (i = 0; i < len; i++) {
1114 zap_leaf_t *l;
1115
1116 if (tbl[i] == lastblk)
1117 continue;
1118 lastblk = tbl[i];
1119
1120 err = zap_get_leaf_byblk(zap, tbl[i], NULL, RW_READER, &l);
1121 if (err == 0) {
1122 zap_leaf_stats(zap, l, zs);
1123 zap_put_leaf(l);
1124 }
1125 }
1126 }
1127
1128 int
fzap_cursor_move_to_key(zap_cursor_t * zc,zap_name_t * zn)1129 fzap_cursor_move_to_key(zap_cursor_t *zc, zap_name_t *zn)
1130 {
1131 int err;
1132 zap_leaf_t *l;
1133 zap_entry_handle_t zeh;
1134
1135 if (zn->zn_key_orig_numints * zn->zn_key_intlen > ZAP_MAXNAMELEN)
1136 return (ENAMETOOLONG);
1137
1138 err = zap_deref_leaf(zc->zc_zap, zn->zn_hash, NULL, RW_READER, &l);
1139 if (err != 0)
1140 return (err);
1141
1142 err = zap_leaf_lookup(l, zn, &zeh);
1143 if (err != 0)
1144 return (err);
1145
1146 zc->zc_leaf = l;
1147 zc->zc_hash = zeh.zeh_hash;
1148 zc->zc_cd = zeh.zeh_cd;
1149
1150 return (err);
1151 }
1152
1153 void
fzap_get_stats(zap_t * zap,zap_stats_t * zs)1154 fzap_get_stats(zap_t *zap, zap_stats_t *zs)
1155 {
1156 int bs = FZAP_BLOCK_SHIFT(zap);
1157 zs->zs_blocksize = 1ULL << bs;
1158
1159 /*
1160 * Set zap_phys_t fields
1161 */
1162 zs->zs_num_leafs = zap->zap_f.zap_phys->zap_num_leafs;
1163 zs->zs_num_entries = zap->zap_f.zap_phys->zap_num_entries;
1164 zs->zs_num_blocks = zap->zap_f.zap_phys->zap_freeblk;
1165 zs->zs_block_type = zap->zap_f.zap_phys->zap_block_type;
1166 zs->zs_magic = zap->zap_f.zap_phys->zap_magic;
1167 zs->zs_salt = zap->zap_f.zap_phys->zap_salt;
1168
1169 /*
1170 * Set zap_ptrtbl fields
1171 */
1172 zs->zs_ptrtbl_len = 1ULL << zap->zap_f.zap_phys->zap_ptrtbl.zt_shift;
1173 zs->zs_ptrtbl_nextblk = zap->zap_f.zap_phys->zap_ptrtbl.zt_nextblk;
1174 zs->zs_ptrtbl_blks_copied =
1175 zap->zap_f.zap_phys->zap_ptrtbl.zt_blks_copied;
1176 zs->zs_ptrtbl_zt_blk = zap->zap_f.zap_phys->zap_ptrtbl.zt_blk;
1177 zs->zs_ptrtbl_zt_numblks = zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks;
1178 zs->zs_ptrtbl_zt_shift = zap->zap_f.zap_phys->zap_ptrtbl.zt_shift;
1179
1180 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks == 0) {
1181 /* the ptrtbl is entirely in the header block. */
1182 zap_stats_ptrtbl(zap, &ZAP_EMBEDDED_PTRTBL_ENT(zap, 0),
1183 1 << ZAP_EMBEDDED_PTRTBL_SHIFT(zap), zs);
1184 } else {
1185 int b;
1186
1187 dmu_prefetch(zap->zap_objset, zap->zap_object,
1188 zap->zap_f.zap_phys->zap_ptrtbl.zt_blk << bs,
1189 zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks << bs);
1190
1191 for (b = 0; b < zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks;
1192 b++) {
1193 dmu_buf_t *db;
1194 int err;
1195
1196 err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
1197 (zap->zap_f.zap_phys->zap_ptrtbl.zt_blk + b) << bs,
1198 FTAG, &db);
1199 if (err == 0) {
1200 zap_stats_ptrtbl(zap, db->db_data,
1201 1<<(bs-3), zs);
1202 dmu_buf_rele(db, FTAG);
1203 }
1204 }
1205 }
1206 }
1207
1208 int
fzap_count_write(zap_name_t * zn,int add,uint64_t * towrite,uint64_t * tooverwrite)1209 fzap_count_write(zap_name_t *zn, int add, uint64_t *towrite,
1210 uint64_t *tooverwrite)
1211 {
1212 zap_t *zap = zn->zn_zap;
1213 zap_leaf_t *l;
1214 int err;
1215
1216 /*
1217 * Account for the header block of the fatzap.
1218 */
1219 if (!add && dmu_buf_freeable(zap->zap_dbuf)) {
1220 *tooverwrite += zap->zap_dbuf->db_size;
1221 } else {
1222 *towrite += zap->zap_dbuf->db_size;
1223 }
1224
1225 /*
1226 * Account for the pointer table blocks.
1227 * If we are adding we need to account for the following cases :
1228 * - If the pointer table is embedded, this operation could force an
1229 * external pointer table.
1230 * - If this already has an external pointer table this operation
1231 * could extend the table.
1232 */
1233 if (add) {
1234 if (zap->zap_f.zap_phys->zap_ptrtbl.zt_blk == 0)
1235 *towrite += zap->zap_dbuf->db_size;
1236 else
1237 *towrite += (zap->zap_dbuf->db_size * 3);
1238 }
1239
1240 /*
1241 * Now, check if the block containing leaf is freeable
1242 * and account accordingly.
1243 */
1244 err = zap_deref_leaf(zap, zn->zn_hash, NULL, RW_READER, &l);
1245 if (err != 0) {
1246 return (err);
1247 }
1248
1249 if (!add && dmu_buf_freeable(l->l_dbuf)) {
1250 *tooverwrite += l->l_dbuf->db_size;
1251 } else {
1252 /*
1253 * If this an add operation, the leaf block could split.
1254 * Hence, we need to account for an additional leaf block.
1255 */
1256 *towrite += (add ? 2 : 1) * l->l_dbuf->db_size;
1257 }
1258
1259 zap_put_leaf(l);
1260 return (0);
1261 }
1262